Exam 2 Flashcards
Shoulder muscles that originate on the vertebral column/skull
Trapezius Rhomboid Major Rhomboid MInor Levator Scapula Latissimus Dorsi
Trapezius
Origin
External occipital protuberance
Superior nuchal line
Ligamentous nuchae
Spines of the thoracic vertebrae (C7-T12)
Trapezius
Insertion
Clavicle
Acromion process and spine of scapula
Trapezius
Actions
Stabilizes scapula
Upper portion: elevates scapula
Middle and lower portions: adduct and depress scapula
Trapezius
nerve supply
Motor: spinal accessory nerve (CN XI)
Sensory: C3, C4
Trapezius Palsy
Deepening of the shoulder on the affected side
Whiplash injury
Beyond tensile strength
-trapezius
Rhomboid Major
Origin
Spines/upper thoracic vertebrae
Rhomboid Major
Insertion
Vertebral border of scapula
Rhomboid minor
Origin
Spines/ lower cervical and first thoracic vertebrae
Rhomboid minor
Insertion
Vertebral border/scapula
Levator scapula
Origin
Transverse processes/upper cervical vertebrae
Levator Scapula
Insertion
Superior angle/scapula
Proximal medial border/scapula
Actions of Rhomboids and Levator Scapula
Elevates scapula
Adducts scapula
Stabilize scapula
Innervation of Rhomboids and Levator Scapula
Dorsal Scapula Nerve (C5)
Damage to Dorsal Scapular Nerve (C5)
Difficulty in complete adducting scapula
Scapula further from midline (on affected side)
Latissimus Dorsi
Origin
Spines/lower thoracic and lumbar vertebrae
Thoracodorsal fascia
Crest/ilium
Lower ribs
Latissimus Dorsi
Insertion
Intertubercular groove (lesser tubercle)/ humerus
Latissimus Dorsi
Actions
Extends humerus
Adducts humerus
Medially rotates humerus
Involved with forced expiration
Latissimus Dorsi
Nerve Supply
Thoracodorsal (C6, C7, C8)
Weakness or damage to latissimus dorsi
Forward displacement of humerus at shoulder joint
Lumbar triangle
Latissimus dorsi
Crest of ilium
External oblique muscle
Clinical significance of lumbar triangle
Hernia of posterior abdominal wall
Triangle of auscultation
Latissimus dorsi, trapezius, vertebral border of scapula
Clinical significance of triangle of auscultation
Easily hear lungs sounds
Serratus anterior
Origin
Upper 8 or 9 ribs
Serratus anterior
Insertion
Vertebral border/scapula
Serratus anterior
Actions
Abducts scapula
Stabilizes scapula
Involved with forced inspiration (only when humerus abducted)
Serratus anterior
Nerve
Long thoracic (C5, C6, C7)
Long thoracic nerve palsy
Aka winged scapula
Serratus anterior is weakened due to damage to nerve
Scapular Muscles
Deltoid Supraspinatus Infraspinatus Subscapularis Teres Major Teres minor
Rotator Cuff Muscles
Supraspinatus
Infraspinatus
Subscapularis
Teres minor
Criteria for Rotator Cuff Muscles
Tendon of insertion must contribute to forming cuff around proximal part of humerus
Participate in either lateral or medial rotation of humerus
Deltoid
Origin
Clavicle
Acromion process
Spine of scapula
Deltoid
Insertion
Deltoid tuberosity/ humerus
Deltoid
Actions
Anterior- flexes and medially rotates humerus
Middle- abducts humerus
Posterior- extends and laterally rotates humerus
Deltoid
Nerve supply
Axillary nerve (C5, C6)
Atrophy of deltoid
Aka Crutch Paralysis
Supraspinatus
Origin
Supraspinatus fossa/ scapula
Supraspinatus
Insertion
Greater tuberosity/ humerus
Supraspinatus
Actions
Initiates abduction of humerus
Laterally rotates humerus
Stabilizes shoulder joint
Supraspinatus
Nerve
Suprascapular (C5, C6)
Tendon of insertion for supraspinatus is separated from acromion process by
Subacromial and subdeltoid bursa
Rotator Cuff Tendonitis
Irritation and inflammation of supraspinatus tendon
Aka shoulder impingement Syndrome
Causes of rotator cuff tendonitis
Genetic Weakness around rotator cuff Excess stress and repetition Trauma/injury Calcium deposits
Rotator cuff Tears
Tendon usually ruptures at or near insertion
Drop test
To evaluate Rotator Cuff Tears
Lower fully abducted limb slowly and limb will drop suddenly to patient’s side in uncontrolled manner if tendon torn
Bursitis in Rotator Cuff
Inflammation of bursa that separates tendon from acromion process (subdeltoid or subacromial)
Infraspinatus
Origin
Infraspinatus fossa/ scapula
Infraspinatus
Insertion
Greater tuberosity/ humerus
Infraspinatus
Actions
Laterally rotates humerus
Stabilizes shoulder joint
Infraspinatus
Nerve
Suprascapular (C5, C6)
Subscapularis
Origin
Subscapular fossa/ scapula
Subscapularis
Insertion
Lesser tuberosity/ humerus
Subscapularis
Actions
Medially rotates humerus
Stabilizes shoulder joint
Subscapularis
Nerve
Upper and lower subscapular nerves (C5, C6)
Teres Minor
Origin
Axillary border/ scapula
Teres minor
Insertion
Greater tuberosity/ humerus
Teres minor
Actions
Laterally rotates humerus
Stabilizes shoulder joint
Teres minor
Nerve
Axillary (C5, C6)
Teres major
Origin
Inferior angle/scapula
Teres major
Insertion
Intertubercular groove/ humerus
Teres major
Actions
Adducts and medially rotates humerus
Stabilizes shoulder joint